1. Field of the Invention
Aspects of the present invention relate to an image forming apparatus, and more particularly, to an image forming apparatus with an improved opening and closing structure.
2. Description of the Related Art
In general, an image forming apparatus (such as a printer, a photocopier, and a facsimile machine) has a cover that opens and closes an upper portion of a body in order to facilitate repair/maintenance of the components provided in the body and/or to remove paper jammed in a paper conveyance path. Such an image forming apparatus requires an opening and closing apparatus to maintain the cover in an open state and a closed state.
A conventional opening and closing apparatus for maintaining a cover in an open state and a closed state is disclosed in Japanese Patent Publication Nos. H8-143054 and H10-98278. However, the opening and closing apparatus disclosed in Japanese Patent Publication Nos. H8-143054 and H10-9872 only has a cover function and is inefficient if the cover is heavy. However, if the cover is provided with an additional device (such as a scanner or an automatic document feeder (ADF)) that adds weight to the cover, there is a problem in maintaining the cover in the open state. As a result, the cover abruptly closes causing damage to the body.
Japanese Patent Publication No. 2006-119474 discloses an image forming apparatus that, despite including a heavy cover unit, is capable of maintaining the cover unit in an open state. The image forming apparatus disclosed in Japanese Patent Publication No. 2006-119474 includes a locking member provided at either an image forming unit or an image reading unit, and a link member having one end supported by the other unit and the other end engaged with the locking member when the image reading unit is in an open state. The link member links both of the units in the open state.
However, the image forming apparatus disclosed in Japanese Publication No. 2006-119474 must include an extension coil spring in order to elastically support the other end of the link member and maintain the link member in an open state. That is, in the absence of the extension coil spring, the up-standing state of the link member is unstable and thus a cover unit is likely to abruptly close during work (such as repair/maintenance or jammed paper removal). In this case, damage to the body and/or injuries to a user's fingers result.